This invention relates primarily to power table saws having a rotatable saw blade, although it is applicable to similar power table tools such as dados, sanders, grinders, shapers, and other such cutting tools where sawdust, chips and dust are created during operation of the tool. The power table saw or other power table tool to which the invention is applicable is mounted below a work table, with a portion of the cutting tool protruding upwardly through a slot or other opening formed in the table. A housing or similar enclosure surrounds the portion of the cutting tool or blade below the table to confine and remove the sawdust, chips or other particles generated by the operation of the tool. Suitable suction or other means may be connected to the interior of the housing for removal therefrom of the sawdust, chips or other particles.
Dust confining and collecting housings or enclosures for power table saws and similar cutting tools are known. Examples may be found in the following U.S. Pat. Nos. 922,840, 1,789,569, 2,044,481, 3,007,501 and 4,063,478.
Heretofore, dust confining and collection housings for power table saws and the like have not been effective in preventing the escape of dust from within the confines of the housing to the ambient atmosphere. This particularly has been true of power tools which have capacity for vertical and/or angular movement relative to a work table. Such movements of the cutting blade or element of the power tool tend to create gaps or clearances between the housing and the table or other element to which the housing abuts, permitting escape of dust from the housing.
A need exists in the use of power table saws and similar tools for a dust confining and collection housing which surrounds the cutting element of such a tool in dust-tight relationship at all times, so as to be 100% efficient, or nearly so, in confining, collecting and removing dust created by the operation of such a tool, regardless of the vertical or angular disposition of the cutting blade.